package com.across.connect.util;

import java.security.MessageDigest;
import java.util.zip.CRC32;


public class EmailHashUtil {

	public static String getEmailHash(String email) {
		CRC32 crc = new CRC32();
		crc.reset();
		crc.update(email.getBytes());
		Long emailCRC = crc.getValue();
		String emailMD5 = MD5(email);
		return emailCRC.toString() + '_' + emailMD5;
	}
	
	private static final char  hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
		'a', 'b', 'c', 'd', 'e', 'f' };
	
	private static final String MD5(String message) {
		try {
			byte[] strTemp = message.getBytes();
			MessageDigest mdTemp = MessageDigest.getInstance("MD5");
			mdTemp.update(strTemp);
			byte[] md = mdTemp.digest();
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++) {
				byte byte0 = md[i];
				str[k++] = hexDigits[byte0 >>> 4 & 0xf];
				str[k++] = hexDigits[byte0 & 0xf];
			}
			return new String(str);
		} catch (Exception e) {
			return null;
		}
	}
}
